Air compressor



Oct.` 8, 1946. v JfE. ERICKSON AIR COMPRESSOR Filed Jan. 29, 1944Y 3 vn0 n.64

' I INVENTOR. John .E E'rzc/rson.

Avro RNEYB Patented Oct. 8, 1946 UNITED STATES PATENT OFFICE AIR COMPRESSOR John E. Erickson, Phoenix, Ariz. Y Application January 29,1944, serial No. 520,281

2 Claims.

This invention relates to air compressors having four o-r more useful applications.

The object of the' invention is to provide an air compressor that can run slowly with very little leakage between its plunger and cylinder walls or through its valves, with the result that there is lower power loss.

In the accompanying drawing and the figures of reference marked thereon which form a part of this specication, I make use of a storage tank lil provided with a pressure responsive switch -I2 electrically connected with a motor I4 for starting and stopping the motor in accordance with predetermined low and high pressure conditions, respectively,in the tank. A belt I5 operatively connects the motor with a crank wheel I8. A link connects the crank wheel with a piston rod 22 of a pump 24. The pump 24 comprises a cylinder 26 having a slidable plunger or piston 28 attached to the piston rod 22. Two ports 30-30 are provided in the piston 28 for the passage of air from the lower part of cylinder to the space above the piston. The ports 30-30 are under control of downwardly seating valves 32-32 hinged to the piston 28` The head 34 of the cylinder 26 has a discharge port 36 under the control of a downwardly seating valve 33 which is housed in al chamber 4B communicating with the storage tankl through a pipe 42. A Water level indicating window 44 is provided in the chamber 4t. Located beneath the piston 28 is a wall 45 attached to the cylinder 26 and provided with an intake port 48 under the control of a downwardly seating hinged valve on the wall 46. To the lower end of the cylinder is connected one end of a gooseneck 52 having its other end connected with an upstanding pipe 54 having its inlet end 56 controlled by a valve 58.

In starting, the water or liquid to be used is poured in slowly into the pipe 54 vthrough the Valve 58 while the pump is running. When water appears in the window of gauge glass 44, the pump is stopped, and the plug 60 isremoved to lower the water in the gooseneck to the level 62. Further draining of the water through a port 60a in the gooseneck will lower the water to the level 64 about one half inch below water level 62. A rubber hose 60h connected to the gooseneck 52 by a coupling 60e is adapted to be held up or down to drain the water and only enough water is retained to supply a shallow amount of water on valve 450 the level of the water on valve 50 being designated at 63. The plunger will pick up some of that water so it will be sealed and when it reaches the top it will force some water through the port '36 so it will have enough water to seal the valve 38. When the rubber hose Bb is employed, a thumb screw 60d threaded in a holder 60e connected, through a swivel connection 60;, with the outer end portion of the hose for selectively adjusting the level thereof with reference to the water level in the gooseneck 52. 65 is a screen to keep out insects. Some drops of water will trickle down through valves 38, 32-32 and 50 while air is passing up through them. This will drain condensed water from the compressed air in the tank I0 down through the valves into the gooseneck and out to waste, through the opening for the plug 60 which is left open at all times except While starting.

When the plunger moves up from the bottom of the cylinder it carries some water on its upper side, and it pulls some water up through opening valve 50 until water level 62 drops to water level B4. Air will not go down through the water, but at 64 it will slide through on top of water and go up through open valve 5l). When the plunger comes down the drops of water falling back down through Valve 50 before it has time to close will raise water level from 64 to 62 again, but

no higher when valve 5D is closed, and no air will go down into the water when the level is up to v62 again.

' ing the diameter of the gooseneck and gauging the distance from water line 54 to 62 which may be only some thousandths of aninch.

I claim:

1. An apparatus of the character described comprising a U-shaped conduit, an upstanding supply conduit connected to one end of said U-shaped conduit and having a valve controlled inlet port, an upstanding pump cylinder connected to the other end of said U-shaped conduit and having an inlet in its bottom end wall, an upwardly opening check valve controlling the passage of fluid through the pump inlet, a piston mounted to reciprocate in the cylinder having a plurality of ports therethrough, downwardly seating check valves mounted on the piston, crank mechanism for actuating the piston, a chamber on the top end wall of the cylinder communicating with the latter through an outlet port, said chamber having a discharge port connecting with a receiver, and an outwardly opening check valve controlling the passage of iiuid through said outlet port, said U-shaped conduit being adapted to contain liquid to a level above the inlet port of the pump and at a lower level in the supply end suitable to draw gaseous uid through the pump inlet and liquid seal the piston and the valve of the pump.

2. In a pumping system, the combination of a storage tank, a vertically disposed pump for pumping air to the tank, a goose neck liquid container connected to the lower end of the pump through an inwardly opening valve, upwardly opening valves carried by the pump piston, a

JOHN E. ERICKSON. 

